1. Field of the Invention
The present invention relates to a method of providing the end plate of a can with a score and a tab for opening the can. More particularly, the invention is concerned with a method of providing the end plate of a can with a score and a tab, wherein the score is charged with a molten thermoplastic resin and the fixed portion of the tab is applied also with a thermoplastic resin.
2. Description of the Prior Art
It is well known to form a score in the end plate of a can in order to facilitate the opening of the can. The score, however, often permits an exudation or leak of the can therethrough undesirably. To avoid this problem, it has been proposed to attach a foil to the portion of the end plate where the score is formed or to press the portion of the end plate where the score is to be formed thereby to reduce the thickness at that portion to facilitate the opening.
The first method, i.e. the attaching of the foil requires a complicated apparatus for supplying and attaching the foil to the scored portion. The second method, i.e. the thinning by pressing makes the portion where the score is to be formed excessively hard, resulting in a reduced toughness.